Hello there,
Thanks for noticing that one - We have indeed rolled out this small enhancement yesterday. We did not plan to add this to release notes until we roll out the rest of the planned enhancements on Team Board. We do however have an in-app guide that is displayed to users on a team board with necessary info (Screen below).
If you did not see this one on a Team Board yesterday - you might get to see it in next few days. Reason for that is we also run an A/B testing on guides to test out their impact on users. Which means you might have been a part of the experiment group - As soon as that experiment ends, you should be able to see it.
To your second point - nothing has changed at this point of time BUT in upcoming weeks, we will be also adding capability to scope board by Releases and Milestones in addition to Iterations (and none scoped Board). Additionally, we will allow users to flip board to a list view and vice versa (Same pattern as Iteration Status page).
On behalf of Rally PM team
Vasek